Those skilled in the art recognize that an average person can improve his or her level of physical fitness by strengthening the back muscles and maintaining flexibility of the spine, and further, that a variety of devices have been developed for such purposes. One such device is designated as 900 and identified as "Prior Art" in FIG. 4. The Prior Art device 900 is a product of Back Technologies, Inc. of Everett, Wash., and is sold under the trademark THE BACK MACHINE.
The Prior Art device 900 includes a generally L-shaped frame 910 extending from a front end 911 to a rear end 912. A relatively longer segment 913 extends upward and rearward from the front end 911 and joins a relatively shorter segment 914, which extends from the common juncture downward and rearward to the rear end 912. A first transverse support 915 is secured to the front end 911, and a second transverse support 916 is secured to the rear end 912. The transverse supports 915 and 916 extend perpendicular to a plane defined by the substantially L-shaped frame 910 and cooperate to support the device 900 relative to a floor surface.
A padded platform 920 is mounted on the relatively longer segment 913 between the front end 911 and the juncture with the relatively shorter segment 914. The padded platform 920 functions as a seat for a user of the device 900. The platform 920 is not adjustable along the length of the frame 910 to accommodate users of different sizes and/or having different needs. Also, no structure other than the first transverse support 915 and/or the floor surface itself is available to support a user's feet.
A spine 930 is mounted on the relatively longer segment 913 between the platform 920 and the juncture with the relatively shorter segment 914. Pairs of rollers 931 and 932 extend from opposite sides of the spine 930, and each of the pairs shares a common axis of rotation. Every other pair of rollers 932 is relatively shorter in length. Adjacent pairs 931 and 932 are arranged relative to one another to define a slight curve that defines a mean angle of approximately 15 degrees relative to the floor surface, and that may be described as upwardly convex relative thereto. The rollers 931 and 932 cooperate to support the back of a user lying backward from a seated position on the platform 920.
A head support 940 is pivotally mounted to the frame 900 proximate the juncture between the relatively longer segment 913 and the relatively shorter segment 914. The head support 940 includes a pair of flanges 941 having three relatively smaller rollers 942 disposed therebetween, and three pairs of relatively larger rollers 943 extending from opposite sides thereof. The rollers 942 and 943 cooperate to support the head of a user lying supine on the rollers 931 and 932.
A linkage 950 extends from the frame 910 to the head support 940 at a distance from their common pivot point. The linkage 950 includes a spring mechanism that resists pivoting of the head support 940 away from the frame 910. The greater the degree of pivoting, the greater the potential energy stored in the spring mechanism 951 which could potential cause injury upon abrupt release thereof.
A U-shaped member 960 is mounted on the relatively shorter segment 914 proximate the rear end 912. The U-shaped member 960 extends upward and slightly rearward from the relatively shorter segment 914. Handles 961 extend from opposite ends of the U-shaped member 960, toward one another and parallel to the second transverse support 916. A user lying supine on the rollers 931 and 932 reaches rearward beyond his or her head and grasps the handles 961 to pull himself or herself rearward over the rollers 931 and 932, typically while also pushing against the floor with his or her feet. The handles 961 also provide a base against which force may be exerted and transmitted through the user's neck to pivot the head support 940 downward and rearward.
Another U-shaped member 970 is mounted on the relatively longer segment 913 beneath the rollers 931 and 932 and proximate the juncture with the shorter segment 914. This U-shaped member 970 extends upward and forward at an angle approximately perpendicular to a plane defined by the other U-shaped member 960. The ends of this U-shaped member 970 terminate in handles 971 that may facilitate mounting and dismounting of the device 900 or perhaps provide a second base against which a user would push rather than pull in order to traverse the rollers 931 and 932 and move the head support 940.
Although suitable in some respects, the Prior Art device 900 nonetheless suffers from certain shortcomings. For example, the device 900 lacks versatility, not only in terms of accommodating users of different sizes and/or having different needs, but also in terms of facilitating more than one specific exercise.
The relatively slight slope of the roller assemblies 931 and 932 relative to the floor surface may prove insufficient for purposes of manipulating and exercising the lower back of some individuals. Furthermore, the spring mechanism 951 requires significant force to be exerted through a person's neck in order to pivot the head support 940 downward, and a sudden release of the accumulated potential energy could result in injury. Moreover, the combination of the spring mechanism 951 and the relatively slight slope of the roller assemblies 931 and 932 results in progressive loading of a person's spine from the head down, which is not only unnatural, but also may place undue strain on a person's neck.
The rollers 942 and 943 on the head support 940 are undesirable because they can tangle and/or pull a person's hair. Also, the head support 940 is not wide enough to support any portion of a person's shoulders. Accordingly, a need remains for an apparatus that satisfactorily exercises and stretches a person's back.